Her "horrible record" raises concerns "so serious we may have to disqualify her from public office," said the editorial. The newspaper credited Clinton's public service, but said "she has an equally long record of obfuscation, secrecy, and working in the shadows to boost her power."

The editorial said "any candidate vying for the votes of the American people needs to have demonstrated a firm commitment to not only the ideal but to the reality of open government."

New Jersey Sen. Cory Booker said on MSNBC that he believes the editorial's assertions "don't fall anywhere near true."

He said during her time as secretary of state, she "worked in Burma and other nations to help create open democracy." He said Clinton has "made a commitment to transparency."

Instances noted by the editorial include Clinton's "clashes over secrecy," as noted in ProPublica, including tax records in 1992, her energy task force in 2006, and disclosures of the Clinton Family Foundation in 2015.

In February, The New York Times called on Clinton to release transcripts of speeches she gave to private Wall Street firms.

Ahead of the Wisconsin presidential primary, the editorial says, "We hope Wisconsin voters give this issue the consideration it deserves when they go to the polls on Tuesday."

The Guardian columnist Jill Abramson said she gets why many see Clinton as less than transparent, because "her first instinct is to withhold."

Abramson said, "Clinton distrusts the press more than any politician I have ever covered." She said she believes Clinton is "fundamentally honest."